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1.
Hum Reprod ; 36(8): 2073-2082, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34097020

RESUMO

STUDY QUESTION: What is the nuclear heterogeneity of high-density purified human spermatozoa typically used for IVF purposes. SUMMARY ANSWER: The data show that while density gradient separation has improved the overall sperm population, there is still a large degree of nuclear heterogeneity within these cells. WHAT IS KNOWN ALREADY: Chromomycin A3 (CMA3) is an important DNA binding fluorochrome for the assessment of male-factor fertility. It is typically used to predict IVF outcomes on entire sperm ejaculates with very high receiver operating characteristic. Here we used CMA3 to characterise typical populations of human spermatozoa that would be used for IVF purposes after density gradient separation. STUDY DESIGN, SIZE, DURATION: We compared the intensity of CMA3 binding within high-dense sperm populations obtained from men. Binding heterogeneity was confirmed through fluorescence microscopy and FACS analysis independently. We also looked at CMA3 staining directly with head morphology in this sperm population. Finally, we looked at electron micrographs of nuclear heterogeneity (vacuoles, chromatin compaction) of spermatozoa following density gradient sorting of CMA3-stained cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: We used sperm donors who had fathered one or more children. Semen was collected after 2 days abstinence and purified over Percoll gradients. Only the high-quality spermatozoa, the same used for assisted conception, were then used. Cells were stained with CMA3 and sorted using FACS. Following this, electron micrographs were used to assess nuclear heterogeneity of CMA3-dependent sorted spermatozoa. MAIN RESULTS AND THE ROLE OF CHANCE: CMA3 staining occurs within morphologically normal as well as abnormal spermatozoa. High-intensity CMA3-stained sperm possessed large vacuoles that were not seen in the low-CMA3 population. In addition, the high-CMA3 stained cells possess higher amounts of nuclear granulation. LIMITATIONS, REASONS FOR CAUTION: The present study only describes the issues within the chromatin of these cells and does not suggest an alternate selection technique. WIDER IMPLICATIONS OF THE FINDINGS: CMA3 is one of the better reported prognostic assays in predicting pregnancy outcomes, especially in cases where the male is at fault. However, it is clear that even in fractionated populations of human spermatozoa, there are sperm cells that are morphologically normal yet possess high levels of CMA3 staining and chromatin granulation. The implication of this is that the embryologist, whom selects on the basis of sperm morphology, may choose a cell with poor chromatin, which may lead to poor embryo outcomes. STUDY FUNDING/COMPETING INTEREST(S): The project was funded by the National Health and Medical Research council, APP1118943. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Masculina , Espermatozoides , Criança , Cromomicina A3 , Fertilização , Humanos , Masculino , Sêmen
2.
Pediatr Transplant ; 21(1)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27699934

RESUMO

The use of lymphocyte-depleting induction immunosuppression has been associated with a reduction in risk of AR after KT among adult recipients, particularly among high-risk subgroups such as AAs. However, data on induction regimen and AR risk are lacking among pediatric KT recipients. We examined outcomes among 7884 first-time pediatric KT recipients using SRTR data (2000-2014). Characteristics were compared across race using Wilcoxon rank-sum tests for continuous and chi-square tests for categorical variables. Risk of AR was estimated using modified Poisson regression, stratified by recipient race, adjusting for recipient age, gender, BMI, primary diagnosis, number of HLA mismatches, maintenance immunosuppression, and donor type. Risk of AR within 1 year was lower in AA recipients receiving lymphocyte-depleting induction (ATG or alemtuzumab; RR, 0.66; 95% CI, 0.52-0.83 P < .001) compared to AA recipients receiving anti-IL-2 receptor antibody induction. This difference was not seen in non-AA recipients receiving lymphocyte-depleting induction (RR, 0.93; 95% CI, 0.81-1.06, P = .26) compared to IL-2 induction. These findings support a role for lymphocyte-depleting induction agents in AA pediatric patients undergoing KT and continued use of IL-2 inhibitor induction in non-AA pediatric KT recipients.


Assuntos
Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Transplante de Rim/métodos , Linfócitos/citologia , Insuficiência Renal/etnologia , Insuficiência Renal/cirurgia , Adolescente , Negro ou Afro-Americano , Alemtuzumab , Anticorpos Monoclonais Humanizados/uso terapêutico , Soro Antilinfocitário/uso terapêutico , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto , Humanos , Lactente , Recém-Nascido , Linfocinas/uso terapêutico , Masculino , Modelos Estatísticos , Reprodutibilidade dos Testes , Risco
3.
J Environ Qual ; 45(6): 1797-1811, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898789

RESUMO

Nitrous oxide (NO) emissions from concentrated animal feeding operations, including cattle feedyards, have become an important research topic. However, there are limitations to current measurement techniques, uncertainty in the magnitude of feedyard NO fluxes, and a lack of effective mitigation methods. The objective of this review was to assess NO emission from cattle feedyards, including comparison of measured and modeled emission rates, discussion of measurement methods, and evaluation of mitigation options. Published annual per capita flux rates for beef cattle feedyards and open-lot dairies were highly variable and ranged from 0.002 to 4.3 kg NO animal yr. On an area basis, published emission rates ranged from 0 to 41 mg NO m h. From these studies and Intergovernmental Panel on Climate Change emission factors, calculated daily per capita NO fluxes averaged 18 ± 10 g NO animal d (range, 0.04-67 g NO animal d). This variation was due to inconsistency in measurement techniques as well as irregularity in NO production and emission attributable to management, animal diet, and environmental conditions. Based on this review, it is clear that the magnitude and dynamics of NO emissions from open-lot cattle systems are not well understood. Further research is required to quantify feedyard NO fluxes and develop cost-effective mitigation methods.


Assuntos
Poluentes Atmosféricos/análise , Ração Animal , Óxido Nitroso/análise , Criação de Animais Domésticos , Animais , Bovinos , Mudança Climática , Dieta , Metano
4.
Mol Ecol ; 23(15): 3695-705, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24033506

RESUMO

Re-introduction of rare species to parts of their historical range is becoming increasingly important as a conservation strategy. Telfair's Skinks (Leiolopisma telfairii), once widespread on Mauritius, were until recently found only on Round Island. There it is vulnerable to stochastic events, including the introduction of alien predators that may either prey upon it or compete for food resources. Consequently, skinks have been introduced to Ile aux Aigrettes, another small Mauritian island that has been cleared of rats. However, the island has been invaded by Asian Musk Shrews (Suncus murinus), a commensal species spread by man well beyond its natural Asian range. Our aim was to use next-generation sequencing to analyse the diets of the shrews and skinks to look for niche competition. DNA was extracted from skink faeces and from the stomach contents of shrews. Application of shrew- and skink-specific primers revealed no mutual predation. The DNA was then amplified using general invertebrate primers with tags to identify individual predators, and then sequenced by 454 pyrosequencing. 119 prey MOTUs (molecular taxonomic units) were isolated, although none could be identified to species. Seeding of cladograms with known sequences allowed higher taxonomic assignments in some cases. Although most MOTUs were not shared by shrews and skinks, Pianka's niche overlap test showed significant prey overlap, suggesting potentially strong competition where food resources are limited. These results suggest that removal of the shrews from the island should remain a priority.


Assuntos
Comportamento Competitivo , Dieta , Lagartos/fisiologia , Comportamento Predatório , Musaranhos/fisiologia , Animais , Fezes/química , Feminino , Conteúdo Gastrointestinal , Espécies Introduzidas , Invertebrados/classificação , Masculino , Maurício , Análise de Sequência de DNA , Especificidade da Espécie
5.
Int J Clin Pract ; 68(2): 203-15, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24355040

RESUMO

BACKGROUND: The association between testosterone deficiency and insulin resistance in men with type 2 diabetes is well established. Current Endocrine Society and European Association of Urology guidelines recommend the measurement of testosterone levels in all men with type 2 diabetes and in men suffering from erectile dysfunction. It is recognised that a range of physical symptoms appear as the testosterone level falls but few studies have addressed the threshold at which symptoms improve with physiological replacement. We report the first double-blind placebo-controlled study conducted exclusively in a male type 2 diabetes population to assess the metabolic changes with testosterone replacement. METHODS: The type 2 diabetes registers of seven general practices were screened to establish the prevalence of low testosterone and the associations with diabetes control. Of 550 eligible patients approached, 488 men (mean age 62.6) consented to take part in screening with a morning testosterone level, assessed between 8 and 11 am. This identified 211 patients for a double-blind placebo-controlled study of long acting testosterone undecanoate (TU) 1000 mg lasting 30 weeks followed by 52 weeks of open label use. The population was divided into a SEVERE group with either total testosterone (TT) of 8 nmol/l or less or free testosterone (FT) 180 pmol/l or less or a MILD group with TT 8.1-12 nmol/l or FT 181-250 pmol/l. RESULTS: Men in the SEVERE group increased mean through TT from 7.73 nmol/l at baseline to 9.93 at 30 weeks and the MILD group from 10.47 to 11.94. The SEVERE group showed marked improvement in sexual function, but no significant improvement in metabolic parameters. The MILD group showed no improvement in sexual function, but significant improvement in weight, body mass index, waist circumference and Hospital Anxiety and Depression Scale. Improvement was seen in all parameters during 52 weeks open label treatment where trough TT levels approached 15 nmol/l. Baseline prostate-specific antigen (PSA) was lower in the SEVERE group and increased with TU for 30 weeks and then stabilised. There was no increase in PSA with treatment in the MILD group. CONCLUSIONS: Testosterone undecanoate significantly improves sexual parameters and Ageing Male Symptom Score, but not metabolic factors at 30 weeks in men with SEVERE testosterone deficiency syndrome (TDS). In men with MILD TDS, significant improvements in metabolic but not sexual parameters were seen, suggesting that there are threshold levels for response to testosterone replacement therapy and that trials of therapy need to achieve sustained therapeutic levels to be effective. PSA showed minor rises, but only for 30 weeks in the SEVERE group.


Assuntos
Androgênios/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Hipogonadismo/tratamento farmacológico , Testosterona/análogos & derivados , Testosterona/deficiência , Adulto , Idoso , Idoso de 80 Anos ou mais , Androgênios/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Método Duplo-Cego , Esquema de Medicação , Humanos , Hipoglicemiantes/uso terapêutico , Hipogonadismo/sangue , Hipogonadismo/complicações , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Testosterona/sangue , Resultado do Tratamento
6.
J Environ Qual ; 43(4): 1125-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25603061

RESUMO

Methane (CH) emissions from enteric fermentation by livestock account for about 2.1% of U.S. greenhouse gas emissions, with beef and dairy cattle being the most significant sources. A better understanding of CH emissions from beef cattle feedyards can help build more accurate emission inventories, improve predictive models, and meet potential regulatory requirements. Our objective was to quantify CH emissions during winter and summer at a typical beef cattle feedyard on the southern High Plains in Texas. Methane emissions were quantified over 32 d in winter and 44 d in summer using open-path lasers and inverse dispersion analysis. Methane per capita emission rate (PCER) ranged from 71 to 118 g animal d in winter and from 70 to 130 g animal d in summer. Mean CH PCER was similar in January, February, and May (average, 85.0 ± 0.95 g animal d) and increased to 93.4 g animal d during the June-July period. This increase coincided with increased dietary fiber. Methane loss ranged from 9.2 to 11.4 g CH kg dry matter intake, with lower values during winter. Gross energy intake (GEI) ranged from 135.2 to 164.5 MJ animal d, and CH energy loss ranged from 4.5 to 4.9 MJ animal d. Fraction of GEI lost as CH (Y) averaged 2.8% in winter, 3.2% in summer, and 3.0% overall. These values confirm the Y value currently recommended by the Intergovernmental Panel on Climate Change for Tier 2 estimates of enteric CH from feedlot fed cattle.

7.
J Environ Qual ; 43(2): 690-700, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25602670

RESUMO

Manure from beef cattle feedyards is a valuable source of nutrients and assists with maintaining soil quality. However, humification and decomposition processes occurring during feedyard manure's on-farm life cycle influence the forms, concentrations, and availability of carbon (C) and nutrients such as nitrogen (N) and phosphorus (P). Improved understanding of manure organic matter (OM) chemistry will provide better estimates of potential fertilizer value of manure from different feedyard sources (e.g., manure accumulated in pens, stockpiled manure after pen scraping) and in settling basin and retention pond sediments. This will also assist with identifying factors related to nutrient loss and environmental degradation via volatilization of ammonia and nitrous oxide and nitrate leaching. We used Fourier-transform infrared (FTIR) and ultraviolet-visible (UV-vis) spectroscopies to characterize structural and functional properties of OM and water-extractable OM (WEOM) from different sources (surface manure, manure pack, settling basin, retention pond) on a typical commercial beef feedyard in the Texas Panhandle. Results showed that as beef manure completes its on-farm life cycle, concentrations of dissolved organic C and N decrease up to 98 and 95%, respectively. The UV-vis analysis of WEOM indicated large differences in molecular weight, lignin content, and proportion of humified OM between manures from different sources. The FTIR spectra of OM and WEOM indicate preferential decomposition of fats, lipids, and proteins over aromatic polysaccharides such as lignin. Further work is warranted to evaluate how application of feedyard manure from different sources influences soil metabolic functioning and fertility.

8.
J Environ Qual ; 43(4): 1159-68, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25603064

RESUMO

Ammonia (NH) volatilization from manure in beef cattle feedyards results in loss of agronomically important nitrogen (N) and potentially leads to overfertilization and acidification of aquatic and terrestrial ecosystems. In addition, NH is involved in the formation of atmospheric fine particulate matter (PM), which can affect human health. Process-based models have been developed to estimate NH emissions from various livestock production systems; however, little work has been conducted to assess their accuracy for large, open-lot beef cattle feedyards. This work describes the extension of an existing process-based model, the Integrated Farm Systems Model (IFSM), to include simulation of N dynamics in this type of system. To evaluate the model, IFSM-simulated daily per capita NH emission rates were compared with emissions data collected from two commercial feedyards in the Texas High Plains from 2007 to 2009. Model predictions were in good agreement with observations and were sensitive to variations in air temperature and dietary crude protein concentration. Predicted mean daily NH emission rates for the two feedyards had 71 to 81% agreement with observations. In addition, IFSM estimates of annual feedyard emissions were within 11 to 24% of observations, whereas a constant emission factor currently in use by the USEPA underestimated feedyard emissions by as much as 79%. The results from this study indicate that IFSM can quantify average feedyard NH emissions, assist with emissions reporting, provide accurate information for legislators and policymakers, investigate methods to mitigate NH losses, and evaluate the effects of specific management practices on farm nutrient balances.

9.
J Environ Qual ; 42(3): 666-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673932

RESUMO

Temperature controls many processes of NH volatilization. For example, urea hydrolysis is an enzymatically catalyzed reaction described by the Arrhenius equation. Diet crude protein (CP) controls NH emission by affecting N excretion. Our objectives were to use the Arrhenius equation to model NH emissions from beef cattle () feedyards and test predictions against observed emissions. Per capita NH emission rate (PCER), air temperature (), and CP were measured for 2 yr at two Texas Panhandle feedyards. Data were fitted to analogs of the Arrhenius equation: PCER = () and PCER = (,CP). The models were applied at a third feedyard to predict NH emissions and compare predicted to measured emissions. Predicted mean NH emissions were within -9 and 2% of observed emissions for the () and (T,CP) models, respectively. Annual emission factors calculated from models underestimated annual NH emission by 11% [() model] or overestimated emission by 8% [(,CP) model]. When from a regional weather station and three classes of CP drove the models, the () model overpredicted annual NH emission of the low CP class by 14% and underpredicted emissions of the optimum and high CP classes by 1 and 39%, respectively. The (,CP) model underpredicted NH emissions by 15, 4, and 23% for low, optimum, and high CP classes, respectively. Ammonia emission was successfully modeled using only, but including CP improved predictions. The empirical () and (,CP) models can successfully model NH emissions in the Texas Panhandle. Researchers are encouraged to test the models in other regions where high-quality NH emissions data are available.


Assuntos
Amônia , Temperatura , Amônia/metabolismo , Ração Animal , Animais , Dieta/veterinária , Proteínas Alimentares/metabolismo
10.
Nat Genet ; 29(2): 160-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11586297

RESUMO

Amyotrophic lateral sclerosis (ALS) and primary lateral sclerosis (PLS) are neurodegenerative conditions that affect large motor neurons of the central nervous system. We have identified a familial juvenile PLS (JPLS) locus overlapping the previously identified ALS2 locus on chromosome 2q33. We report two deletion mutations in a new gene that are found both in individuals with ALS2 and those with JPLS, indicating that these conditions have a common genetic origin. The predicted sequence of the protein (alsin) may indicate a mechanism for motor-neuron degeneration, as it may include several cell-signaling motifs with known functions, including three associated with guanine-nucleotide exchange factors for GTPases (GEFs).


Assuntos
Esclerose Lateral Amiotrófica/genética , Genes Recessivos , Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA , Feminino , Ligação Genética , Fatores de Troca do Nucleotídeo Guanina/química , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Transdução de Sinais
11.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37343300

RESUMO

Calf-fed Holstein steers (n = 115; 449 ± 20 kg) were utilized in a serial harvest experiment. A baseline group of five steers was harvested after 226 d on feed (DOF), which was designated day 0. The remaining cattle were assigned randomly to 11 harvest groups, with slaughter every 28 d. Cattle were either not (CON) or were fed zilpaterol hydrochloride for 20 d followed by a 3 d withdrawal (ZH). There were five steers per treatment in each slaughter group ranging from days 28 to 308. Whole carcasses were divided into lean, bone, internal cavity, hide, and fat trim components. Apparent mineral retention (Ca, P, Mg, K, and S) within the body was calculated as the difference between mineral concentration at slaughter and day 0. Mineral concentration at day 0 was determined from body composition of steers harvested at day 0 multiplied by individual live body weight (BW) at day 0. All data were analyzed as a 2 × 11 factorial arrangement with individual animal as the experimental unit. Orthogonal contrasts were used to analyze linear and quadratic contrasts over time (11 slaughter dates). There were no differences in concentration of Ca, P, and Mg in bone tissue as feeding duration increased (P ≥ 0.89); concentration of K, Mg, and S in lean tissue did fluctuate across DOF (P < 0.01). Averaged across treatment and DOF, 99% of Ca, 92% of P, 78% of Mg, and 23% of S present in the body were in bone tissue; 67% of K and 49% of S were in lean tissue. Expressed as gram per day, apparent retention of all minerals decreased linearly across DOF (P < 0.01). Expressed relative to empty body weight (EBW) gain, apparent Ca, P, and K retention decreased linearly as BW increased (P < 0.01) whereas Mg and S increased linearly (P < 0.01). Apparent retention of Ca was greater for CON cattle (greater bone fraction) and apparent retention of K was greater for ZH cattle (greater muscle fraction) when expressed relative to EBW gain (P ≤ 0.02), demonstrating the increase in lean gain by ZH cattle. There were no differences in apparent retention of Ca, P, Mg, K, or S due to treatment (P ≥ 0.14) or time (P ≥ 0.11) when expressed relative to protein gain. Apparent retention averaged 14.4 g Ca, 7.5 g P, 0.45 g Mg, 1.3 g K, and 1.0 g S/100 g protein gain. Expressing apparent mineral retention on a protein gain basis minimized effects of rate and type of gain, allowing for better comparison across treatments and time. Feeding zilpaterol hydrochloride did not affect apparent mineral retention when expressed relative to protein gain.


Mineral requirements for feedlot cattle are largely based on measured mineral concentration in the body at harvest. Fairly extensive research has been done quantifying Ca and P in the body of cattle, but data on Mg, K, and S are sparse. Serial harvest experiments are expensive and labor intensive and therefore not conducted frequently. A group of 115 Holstein steers was fed a finishing diet with serial harvest every 28 d. Two treatments were evaluated, control and cattle fed zilpaterol hydrochloride to increase lean tissue growth. Every 28 d, five steers from each treatment group were harvested with the whole carcass divided into lean, bone, internal cavity, hide, and fat trim components. Apparent mineral retention was calculated as the difference between mineral composition at day 0 (baseline harvest group) and each 28 d harvest group. Averaged across treatment and days on feed, 99% of Ca, 92% of P, 78% of Mg, and 23% of S present in the body were measured in bone tissue; 67% of K and 49% of S were in lean tissue. Apparent retention averaged 14.4 g Ca, 7.5 g P, 0.45 g Mg, 1.3 g K, and 1.0 g S/100 g protein gain.


Assuntos
Ração Animal , Dieta , Animais , Bovinos , Ração Animal/análise , Composição Corporal , Peso Corporal , Dieta/veterinária , Minerais/farmacologia , Compostos de Trimetilsilil/farmacologia , Aumento de Peso
12.
BMC Microbiol ; 12: 25, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22364310

RESUMO

BACKGROUND: The high demand for ethanol in the U.S. has generated large stocks of wet distillers grains (DG), a byproduct from the manufacture of ethanol from corn and sorghum grains. Little is known, however, about the potential influence of dietary DG on fecal microbial community structure. A better understanding of the microbial population in beef cattle feces could be an important monitoring tool to facilitate goals of improving nutrient management, increasing animal growth performance and decreasing odors and/or shedding of pathogens. Five diets consisting of a traditional diet fed to finishing beef cattle in the Southern High Plains of Texas-CON (steam-flaked corn control with 0% DG), and four concentrations of DG in the dietary dry matter; 10 C (10% corn-based DG), 5S (5% sorghum-based DG), 10S (10% sorghum DG), and 15S (15% sorghum DG) were fed to steers at the Texas Tech University Burnett Animal Center. Diets were essentially isonitrogenous with a formulated crude protein value of 13.5%. RESULTS: Fecal grab samples were obtained from 20 steers (n = 4 per diet) and the barcoded DNA pyrosequencing method was used to generate 127,530 16S operational taxonomic units (OTUs). A total of 24 phyla were observed, distributed amongst all beef cattle on all diets, revealing considerable animal to animal variation, however only six phyla (core set) were observed in all animals regardless of dietary treatment. The average abundance and range of abundance, respectively of the core phyla were as follows: Firmicutes (61%, 19 to 83%), Bacteroidetes (28%, 11 to 63%), Proteobacteria (3%, 0.34 to 17.5%), Tenericutes (0.15%, 0.0 to 0.35%), Nitrospirae (0.11%, 0.03 to 0.22%), and Fusobacteria (0.086%, 0.017 to 0.38%). Feeding DG-based diets resulted in significant shifts in the fecal microbial community structure compared with the traditional CON. Four low abundance phyla significantly responded to dietary treatments: Synergistetes (p = 0.01), WS3 (p = 0.054), Actinobacteria (p = 0.06), and Spirochaetes (p = 0.06). CONCLUSIONS: This is, to our knowledge, the first study using this method to survey the fecal microbiome of beef cattle fed various concentrations of wet DG. Comparison of our results with other cattle DNA sequencing studies of beef and dairy cattle feces from a variety of geographical locations and different management practices identifies a core set of three phyla shared across all cattle. These three phyla, in order of relative abundance are; Firmicutes, Bacteroidetes, and Proteobacteria. The presence of large animal-to-animal variation in cattle microbiome was noted in our study as well as by others.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biota , Dieta/métodos , Fezes/microbiologia , Animais , Bactérias/genética , Bovinos , Análise por Conglomerados , Código de Barras de DNA Taxonômico , Grão Comestível/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Am J Ophthalmol Case Rep ; 27: 101578, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35599947

RESUMO

Purpose: To report a case of a 34-year-old female patient with newly diagnosed Maternally Inherited Diabetes and Deafness (MIDD) in the setting of undifferentiated macular dystrophy and newly discovered diabetes. Observations: A 34-year-old woman presented to the retina service with new-onset diabetes and a history of hydroxychloroquine use. Ophthalmologic examination showed findings early in the patient's presentation that within the context of her recent diabetes diagnosis and family history pointed to MIDD as the specific cause of the patient's many different symptoms. This diagnosis was further supported through obtaining previous ophthalmic images of the patient's mother demonstrating circular areas of geographic atrophy seen in advanced MIDD, and the diagnosis was confirmed through genetic testing. Conclusions and importance: As was observed in the patient discussed in this manuscript, recognition of macular dystrophy findings suggestive of MIDD can hasten a timely diagnosis for a patient with diabetes of unspecified etiology. Additionally, knowledge of the underlying cause being MIDD can optimize care for patients in terms of treatment, understanding their risk for various diabetes complications, screening for additional systemic manifestations, and initiating valuable genetic counseling for patients and their families. Given these factors and the surprisingly high prevalence of MIDD among diabetes patients, increased awareness of MIDD and its manifestations can help to optimize diagnosis and management for these patients.

14.
J Anim Sci ; 100(3)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034122

RESUMO

Reliable predictions of metabolizable energy (ME) from digestible energy (DE) are necessary to prescribe nutrient requirements of beef cattle accurately. A previously developed database that included 87 treatment means from 23 respiration calorimetry studies has been updated to evaluate the efficiency of converting DE to ME by adding 47 treatment means from 11 additional studies. Diets were fed to growing-finishing cattle under individual feeding conditions. A citation-adjusted linear regression equation was developed where dietary ME concentration (Mcal/kg of dry matter [DM]) was the dependent variable and dietary DE concentration (Mcal/kg) was the independent variable: ME = 1.0001 × DE - 0.3926; r2 = 0.99, root mean square prediction error [RMSPE] = 0.04, and P < 0.01 for the intercept and slope. The slope did not differ from unity (95% CI = 0.936 to 1.065); therefore, the intercept (95% CI = -0.567 to -0.218) defines the value of ME predicted from DE. For practical use, we recommend ME = DE - 0.39. Based on the relationship between DE and ME, we calculated the citation-adjusted loss of methane, which yielded a value of 0.2433 Mcal/kg of dry matter intake (DMI; SE = 0.0134). This value was also adjusted for the effects of DMI above maintenance, yielding a citation-adjusted relationship: CH4, Mcal/kg = 0.3344 - 0.05639 × multiple of maintenance; r2 = 0.536, RMSPE = 0.0245, and P < 0.01 for the intercept and slope. Both the 0.2433 value and the result of the intake-adjusted equation can be multiplied by DMI to yield an estimate of methane production. These two approaches were evaluated using a second, independent database comprising 129 data points from 29 published studies. Four equations in the literature that used DMI or intake energy to predict methane production also were evaluated with the second database. The mean bias was substantially greater for the two new equations, but slope bias was substantially less than noted for the other DMI-based equations. Our results suggest that ME for growing and finishing cattle can be predicted from DE across a wide range of diets, cattle types, and intake levels by simply subtracting a constant from DE. Mean bias associated with our two new methane emission equations suggests that further research is needed to determine whether coefficients to predict methane from DMI could be developed for specific diet types, levels of DMI relative to body weight, or other variables that affect the emission of methane.


Assuntos
Ingestão de Energia , Metano , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Metabolismo Energético , Modelos Lineares
15.
Curr Opin Cell Biol ; 7(1): 55-64, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7755990

RESUMO

Organelles of the central membrane system of higher eukaryotes have been shown to utilize microtubules both for maintenance of their characteristic spatial distributions and for efficient transport of their protein and lipid to diverse sites within the cell. Recent work addressing the mechanisms that underlie this organization provides new insights regarding the roles of microtubules and microtubule motors in influencing organelle dynamics and specific membrane traffic routes through the cytoplasm.


Assuntos
Membranas Intracelulares/metabolismo , Microtúbulos/metabolismo , Organelas/ultraestrutura , Animais , Transporte Biológico/fisiologia , Endossomos/metabolismo , Endossomos/ultraestrutura , Células Eucarióticas , Membranas Intracelulares/ultraestrutura , Microtúbulos/ultraestrutura , Fosforilação
16.
Nat Cell Biol ; 2(5): 288-95, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10806480

RESUMO

When co-translationally inserted into endoplasmic reticulum (ER) membranes, newly synthesized proteins encounter the lumenal environment of the ER, which contains chaperone proteins that facilitate the folding reactions necessary for protein oligomerization, maturation and export from the ER. Here we show, using a temperature-sensitive variant of vesicular stomatitis virus G protein tagged with green fluorescent protein (VSVG-GFP), and fluorescence recovery after photobleaching (FRAP), the dynamics of association of folded and misfolded VSVG complexes with ER chaperones. We also investigate the potential mechanisms underlying protein retention in the ER. Misfolded VSVG-GFP complexes at 40 degrees C are highly mobile in ER membranes and do not reside in post-ER compartments, indicating that they are not retained in the ER by immobilization or retrieval mechanisms. These complexes are immobilized in ATP-depleted or tunicamycin-treated cells, in which VSVG-chaperone interactions are no longer dynamic. These results provide insight into the mechanisms of protein retention in the ER and the dynamics of protein-folding complexes in native ER membranes.


Assuntos
Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Glicoproteínas de Membrana , Dobramento de Proteína , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Antibacterianos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Células COS , Ditiotreitol/farmacologia , Genes Reporter , Glicosilação , Proteínas de Fluorescência Verde , Indicadores e Reagentes/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Temperatura , Tunicamicina/farmacologia
17.
J Environ Qual ; 40(4): 1090-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21712577

RESUMO

Ammonia emitted from beef cattle feedyards adds excess reactive N to the environment, contributes to degraded air quality as a precursor to secondary particulate matter, and represents a significant loss of N from beef cattle feedyards. We used open path laser spectroscopy and an inverse dispersion model to quantify daily, monthly, seasonal, and annual NH emissions during 2 yr from two commercial cattle feedyards in the Panhandle High Plains of Texas. Annual patterns of NH fluxes correlated with air temperature, with the greatest fluxes (>100 kg ha d) during the summer and the lowest fluxes (<15 kg ha d) during the winter. Mean monthly per capita emission rate (PCER) of NH-N at one feedyard ranged from 31 g NH-N head d (January) to 207 g NH-N head d (October), when increased dietary crude protein from wet distillers grains elevated emissions. Ammonia N emissions at the other feedyard ranged from 36 g NH-N head d (January) to 121 g NH-N head d (September). Monthly fractional NH-N loss ranged from a low of 19 to 24% to a high of 80 to 85% of fed N at the two feedyards. Seasonal PCER at the two feedyards averaged 60 to 71 g NH-N head d during winter and 103 to 158 g NH-N head d during summer. Annually, PCER was 115 and 80 g NH-N head d at the two feedyards, which represented 59 and 52% of N fed to the cattle. Detailed studies are needed to determine the effect of management and environmental variables such as diet, temperature, precipitation, and manure water content on NH emissions.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Bovinos/metabolismo , Indústria de Laticínios , Ração Animal , Criação de Animais Domésticos , Animais , Dieta/veterinária , Esterco/análise , Modelos Biológicos , Nitrogênio/análise , Estações do Ano , Análise Espectral , Texas , Tempo (Meteorologia)
18.
Am J Ophthalmol Case Rep ; 23: 101166, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34386641

RESUMO

PURPOSE: To use new adaptive optics scanning laser ophthalmoscopy (AOSLO) technology to better image macular pathology in poppers maculopathy. OBSERVATIONS: A 40-year-old patient was found to have poppers maculopathy. Best corrected visual acuity was decreased to 20/40 OD and 20/50 OS, spectral domain optical coherence tomography found outer retinal disruption of the fovea, and AOSLO imaging showed significant decrease in cone density of the fovea of both eyes. CONCLUSIONS AND IMPORTANCE: Poppers maculopathy is a rare, but visually significant, complication of popper abuse. AOSLO technology demonstrates significant cone damage in poppers maculopathy. The striking loss of cones revealed by AOSLO imaging shows how AOSLO imaging can elucidate macular pathology.

19.
J Ophthalmol ; 2021: 6641008, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104482

RESUMO

The purpose of this study was to assess outcomes in a real-world nonclinical trial setting of antivascular endothelial growth factor (VEGF) injections alone vs. focal laser combined with anti-VEGF injections in patients with branch retinal vein occlusion- (BRVO-) related macular edema (ME). This study included 88 BRVO with ME patients who were treated over three years at both a tertiary referral center in the Birmingham metropolitan area and satellites in rural Alabama. One group received only anti-VEGF injections (n = 56); the other group received both anti-VEGF injections and focal laser (n = 32). The following outcome measures were evaluated: initial and final visual acuities (VA), initial central subfield thickness (CST) on OCT, number of injections, number of lasers, percentage of patients with a gain of 3 lines of VA, percentage of patients with VA better than or equal to 20/40, and percentage of patients with VA worse than or equal to 20/200. We found that there was no difference in initial VA (p=0.913) or CST (p=0.961) between the two groups. The injection only group required a median of 7 injections, while the combination group required a median of 4 injections, but this was not a statistically significant difference (p=0.117). There was no difference in final VA (p=0.414) or any of the other visual outcomes between the two groups. In conclusion, focal laser did not decrease the number of injections required or improve the VA in BRVO-related ME. Although visual outcomes were similar in both groups, focal laser does not appear to be of additional benefit in BRVO-related ME in the anti-VEGF era.

20.
Int J Clin Pract ; 64(7): 925-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20584225

RESUMO

INTRODUCTION: Few studies have addressed the health economics of the provision of services for sexual dysfunction within the National Health Service. AIM: To evaluate the referral patterns, workload and prescribing costs in secondary care resulting from government guidance on erectile dysfunction (ED). METHOD: A review of 324 consecutive referral letters to the Good Hope Hospital Erectile Dysfunction Clinic was conducted to assess the purpose of referral. Prescribing data and costs were assessed over the same 2-year period. RESULTS: Severe distress was the main reason for referral in 54% of referrals. Long term prescribing according to government guidance doubled the cost of care and created an unsustainable increase in clinic and pharmacy workload. CONCLUSIONS: Existing regulations designed to control costs of ED therapy have created health inequalities, waste of resources and have increased the overall cost of care.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Disfunção Erétil/terapia , Encaminhamento e Consulta/estatística & dados numéricos , Assistência Ambulatorial/economia , Custos e Análise de Custo , Inglaterra , Disfunção Erétil/economia , Disparidades em Assistência à Saúde , Humanos , Masculino , Honorários por Prescrição de Medicamentos , Encaminhamento e Consulta/economia , Medicina Estatal/economia , Estresse Psicológico/economia , Estresse Psicológico/etiologia , Carga de Trabalho
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